Wrist-pin inserting tool



1931. H. w. KULP ET AL WRIST PIN INSERTING TOOL Filed May 29. 1930 Ewen/fora;

said pilot portion Patented Oct. 6, 1931 when STATES PATENT OFFICE HARRY W. KULP AND MARTIN G. DELLINGER, OF LANCASTER, PENNSYLVANIA WRIST-PIN msnnrme roor.

Application filed May 29, 1930. Serial No. 457,028.

This invention relates to wrist-pin and similar tubular element inserters and removers and is primarily intended for use in connection with internal combustion engines to center a wrist-pin in the tool and to then either drive out such wrist-pin from a connecting-rod or to, as a single continuous operation, spread a split-ring form spring wrist-pin retainer, or to radially displace some element or part from the path followed by the wrist-pin during insertion, and to properly position the wrist-pin in the connecting-rod, which wrist-pin in the form illustrated is formed with an annular groove which registers with, and receives a portion of, said retainer when said wristpin is in proper operative position in the connecting-rod.

The primary objects of this invention are, to provide an efficient tool having a pilot block or portion for cooperating with an external peripheral end face of such a wristpin to properly center it with particular relation to the cooperating external face of for easy and expeditious insertion; to provide said tool with a slidably removable pilot block or sleeve having a tapering external face portion for engaging the retainer and displacing it radially out of the bore in said connecting-rod; to provide the larger end of said pilot-sleeve with an annular concave or conical shoulder or face to engage the radially outer peripheral face of the adjacent end portion of said wrist-pin to properly center the same, said large end of said pilot-sleeve being of the same diameter as said wrist-pin or substantially so and said concave or conical shoulder preferably making a knife edge, or substantially knife edge with the annular external shoulder of the adjacent portion of said pilot block or sleeve; to provide in such a tool a driving portion or shank provided on its inner or driving end with an annular shoulder or face concentric with, and extending perpendicularly to, its axis and adapted to bear against one end of the wirst-pin and to be held in such engagement by means sleeve and their connecting stem and co- .rior and exterior faces of all wrist-pins used of said pilot block or c operating nut, said driving portion or shank having its outer end slightly rounded off to receive hammer blows to force the wristpin out of the connecting-rod or to, by gentle hammer blows, aid in properly positioning the wrist-pin in the connecting-rod, said driving portion or shank also functioning as a backing or stop to prevent axial movement of the wrist-pin while being centered in said tool preliminary to insertion in said connecting-rod; to provide in such a tool means for forcing the pilot block or sleeve in an axial direction during the centering of said wrist-pin with relation thereto, while avoiding a rotary movement of either or both of said block or sleeve and said wristpin to facilitate the centering operation; and to provide a very simple, sturdy and efficient tool for this purpose which will stand considerable abuse without impairing its efficiency, and which is economical of manufacture and is capable of being manufactured on a large production basis and for the most part by present known automatic machinery.

A popular make of automobile now in extensive use throughout the world employs a tubular wrist-pin having an annular groove in its exterior cylindrical face and equidistant from its ends and apparently formed from stock tubing, the outer face being trued up and the inner face apparently merely roughed out, so that there is no general uniform relation between the intein said make of automobile, in practically all of such wrist-pins the interior cylindrical face is eccentric to the exterior cylindrical face, but the degree of such eccentricity will vary more or less as between any two given wrist-pins, but the exterior end-portions of each wrist-pin are rounded off or curved in an axial direction, the curve in an axial direction of said end portions being uniform,

or substantially so, as to all said wrist-pins though it is not essential to the proper oper ation and functioning of our invention that they should be so.

In this application we show and describe only the present preferred embodiment of our invention simply by way of illustration of the practice thereof, as by law required. However, we realize our invention is capable of other and different embodiments, and that the various details thereof may be modified in a number of ways, all without departing from our said invention. Therefore, we wish it understood that the drawing and description herein are to be considered as merely illustrative and not as exclusive.

In the accompanying drawings:

Figure 1 represents an elevation of an embodiment of our invention in use in either inserting a wrist-pin in, or removing a wrist-pin from, a piston and connecting-rod both shown in cross section; the use of a hammer being illustrated;

Figure 2, a view partly in section and partly in elevation of said embodiment as applied to a wrist-pin, said section being taken on a line corresponding to line 3-3 of Fig. 4;

Figure 3, a sectional view taken on line 33 of Fig. 4, the pilot block or sleeve and the driving head or shank being slightly separated from the ends of the wrist-pin;

Figure 4, a sectional view on line H of Fig. 3 to bring out the eccentricity between the inner and outer faces of the wristpin;

Figure 5, a detail sectional view on line 55 of Fig. 3, looking in the direction of the arrows; and

Figure 6, a detail sectional view 011 the line 6-6 of Fig. 3, looking in the-direction of the arrows.

Referring now in detail to the drawings, A designates a piston of conventional con struction, B the connecting-rod, C the wristpin annularly grooved as at D to receive the inner portion of the split-ring spring retainer E disposed in the registering annular groove F in the wall of the bore through the upper end portion of the connecting-rod and radially displaced from said bore into said groove F prior to the passage of the end portion of said wrist-pin C beyond the near wall of groove F during insertion of said wrist-pin, and contracting so as to protrude into said groove D in the wrist-pin when the latter has been completely inserted. The wrist-pin C makes a snug fit in the bearing or bore in the upper end of the connecting-rod B and in the bearings 01 of the piston A, as illustrated in Fig. 1, and as is usual.

The construction set forth in the immediately above paragraph forms no part of our present invention, but its illustration and brief description serves to make the operation and functions of our invention more readily understandable.

In the illustrated embodiment of our invention 1 designates a preferably uniform diameter cylindrical driving portion or shank having a central axial bore receiving an axially extending reduced diameter stem 6 preferably permanently secured therein as by welding, shrinking on or other usual known method of permanent association or connection as to be operatively integral. It is not essential that these two parts shall be formed of separate pieces, though by having them of separate pieces it is practical to use standard sizes of stock material obtainable in the general market without need for extensive manufacturing operations other than truing up. Also, while it is preferred, it is not essential that said two parts shall be opcratively integral or permanently inseparably associated.

Said driving portion or shank 1 has its inner end face formed with an annular shoulder or face 5a extending perpendicularly to the axis of the driving head or shank 1 and extending radially inward from the cylindrical external face 4 of said shank l for a distance in excess of the greatest thick ness of the wall of the wrist-pin C, as well illustrated in Fig. 6, so as to permit the flat seating thereagainst of the adjacent end of said wrist-pin C to hold the latter so that its axis will be parallel to, or coincident with, the axis of said shank 1.

The external face of said shank or driving head 1 will have its inner end portion of the same, or substantially the same, diameter as the external diameter of said wrist-pin C so as to fully en age the end thereof and so as to pass into the wrist-pin bores in the piston A and connecting-rod B, and will preferably be of the same uniform diameter for its full length, with diametrically opposite parallel flattened portions 1a. at its extreme outer end portion for insertion between the jaws of a vise, not shown, or to facilitate gripping by a wrench, not shown, and the extreme end edge of the outer end of said shank or driving head 1 will preferably be rounded off as shown to prevent mashing over or spreading out or chipping off under carelessly applied hammer blows, though, of course, a cushion type hammer, such as a raw-hide hammer or mallet con ventionally indicated by hammer Or should be applied in any such hamn'iering.

It not essential, however, that the shank or driving head 1 shall be of uniform diameter, or that it shall be cylindrical, or that its annular shoulder or face 511 shall be of continuous unbroken area in a peripheral direction, or that said shank 1 shall not have a portion having a greater cross-sectional dimension than the external diameter of said wrist-pin C, or that at all portions it shall have any dimension equal to the external diameter of said Wrist-pin C.

The pilot block or sleeve 2 is to be slipped over the extending screw-threaded end por- Sii tion 6a of the stem 6 and slipped axially of said stem 6 with the concave or conical centering face or shoulder 5 of said block orsleeve 2 opposed to the annular shoulderoa of the driving head or shank 1, theshoulder 5a serving as an abutment, backing or stop for the extreme end edge or face of the interposed wrist-pin C and engaging the same in a plane perpendicular to the axes of said shank 1 and of said wrist-pin C, and the shoulder 5 serving to engage the. radially outer peripheral end edge portion of said wrist-pin C to center the external face of said wrist-pin C with relation to the adjacent portion ofthe external face of the pilot block or sleeve 2. Such association of the wrist-pin C, and the shank 1 and block or sleeve 2 with the stem 6 extending through the wrist-pin C and the pilot block or sleeve 2 and with the screw-threaded portion 6a of stem 6 protruding beyond the smaller end of the pilot block or sleeve 2 may be accomplished by first slipping the wrist-pin C over the end of the stem 6 with a single straight motion, and next slipping the pilot block or sleeve 2 on the stem 6 with a similar single straight endwise motion, with no occasion for any turning or relative rotary movement between any of said parts such as is necessary in screwing one part on another.

When thus assembled the nut 7 is applied to the screw-threaded portion 6a and turned up thereon to engage the adjacent smaller end of the pilot block or sleeve 2 and force the same axially against the wrist-pin C and the latter firmly against the annular face or shoulder 5a of shank or driving head 1, so perfecting the proper centering of the wrist-pin C with relation to the pilot block or sleeve 2 and firmly clamping said wristin G in centered position in the tool.

The pilot block or sleeve 2 has an internal preferably smooth central axial bore of such 1 size as to make a snug sliding fit on the stem 6 and preferably has its external face formed in two portions, said portions being a cylindrical portion 4 extending from its inner end and being of the same external diameter as the external diameter of the wrist-pin C, and a frusto-conical portion 3 tapering axially radially inward from the outer end of said cylindrical portion 4 to the smaller end of the pilot-sleeve 2, said frusto-conical or tapering portion 3 having its largest diameter extreme inner end portion of the same external diameter as said cylindrical portion 4 and wrist-pin C. Obviously, it is not essential that there be any cylindrical face portion 4.

Also, it is not essential that the concave or conical centering face 5 shall be a continnous uninterrupted face in a peripheral direction, it being sufficient if there be similarly formed or profiled portions corresponding to a cross-section through a porion of face 5 and concentrically spaced ,about the axis of sleeve 2 on opposite sides thereof. Also, it is not essential that the frusto-conical face 8, or the cylindrical face 4 if it be present,-shall be continuous and uninterrupted in a peripheral direction, it sufficing if there be left portions of the face 3, or of faces 3 and 4 if face 4 be present, disposed at the same radial distance from the axis of the sleeve or block 2 and on opposite sides thereof.

The parts 1, 2 and 6 will be formed and assembled with as great exactitude or precision as is compatible to economical large quantity production and usual to a tool of this general class, but the tool is not intended as an exact precision instrument down to one ten-thousandths of an inch, nor anything like that degree of precision, there will be some variation, and this specification is to be read with that fact in mind.

The nut 7 will preferably be cylindrical and of the same external diameter as the smaller end of the pilot block or sleeve 2, with its inner face parallel to the opposed smaller face of said pilot block or sleeve 2 and perpendicular to the axis of said nut 7 and block or sleeve 2 and stem 6, and will have its outer end portion formed with two diametrically opposite flattened portions 7a to receive a wrench, not shown, and may have its medial portion knurled or roughened as indicated at 7 b to be easily gripped and turned by hand.

The centering face 5 may be well defined as a concave or conical face extending axially outwardly toward the smaller end of block or sleeve 2 and converging radially inwardly, the radially outer portion of said face merging with or theoretically intersecting the external face of the block or sleeve 2. Since the intersection or approach of said centering means or face to the external face of the block or sleeve 2 would result in the forming of a knife edge as a practical matter said centering means or face 5 may not extend absolutely and exactly to said external face of the block or sleeve 2, but it will preferably approach close thereto as practicable. 1 Said centering means or face 5 may, and preferably will, be in the form of the wall of a continuous groove, but, as stated, this is not essential.

We claim:

1. A tool for inserting a tubular element in a bore and displacing a part in a radial direction from said bore, said tool comprising a stem adapted to extend through said tubular element, and a part immovable with relation to said stem and adapted to engage the adjacent end face of said tubular element at a plurality of points concentric with, and on opposite sides of, its axis and in a single plane perpendicular to the axis of said tuto maintain said tubular element in bular element, in combination with a pilotsleeve adapted to be fitted endwise on said stem and making a snug sliding fit thereon, said sleeve having a frusto-conical external face and having its portion of greatest external diameter presented toward said immovable part and of substantially the same external diameter as said tubular element interposed between said immovable part and said pilot-sleeve, there being an axially outwardly extending radially inwardly con verging centering face formed in the inner end face of said pilotsleeve concentric with the axis thereof and extending from the external peripheral face thereof and being adapted to engage the external peripheral face of the adjacent end of said tubular ele ment to center the same, said stem having its free end portion screw-threaded and adapted to protrude axially beyond said pilot sleeve, and a nut adapted to be turned on said screw-threaded portion of said stem to engage said pilot-sleeve and move the latter axially toward said immovable part to clamp said tubular element between said pilot-sleeve and immovable part and to maintain said tubular element in proper centered relation with said pilot-sleeve.

2. A tool for inserting a tubular element in a bore and displacing a part in a radial direction from said bore, said tool comprising a stem adapted to extend through said tubular element, and a stop carried by said stem and adapted to engage the adjacent end face of said tubular element at a plurality of points concentric with, and on opposite sides of, its axis and in a single plane perpcndicular to the axis of said tubular element, in combination with a pilot-sleeve adapted to make a snug fit on said stem and to be freely slidable axially thereof, said sleeve having a frusto-conical external face and having its portion of greatest external diameter presented toward said stop and of :ail'istantially the same external diameter as said tubular element interposed between said stop and pilot-sleeve, there being an axially outwardly extending radially inwardly converging centering face formed in the inner end face of said pilot-sleeve concentric with the axis thereof and extending from the external peripheral face thereof and being adapted to engage the external peripheral face of the adjacent end of said tubular element to center the same, and means adapted to engage said stem and said pilot-sleeve to move the latter axially toward said stop to clamp said tubular element between said pilot-sleeve and stop and proper centered relation with said pilot-sleeve.

3. A tool for inserting a tubularelement in a bore and displacing a part in a radial direction from said here, said tool comprising a stem adapted to extend through said tubular element, and engaging means carried by said stem and adapted to engage the adjacent end face of said tubular element at a plurality of points concentric with, and on opposite sides of, its axis and in a single plane perpendicular to the axis of said tubular element, in combination with a pilotblock adapted to make a snug fit on said stem and freely slidable axially thereof, said block having an axially tapering external face and having its portion of greatest crosssectional dimension presented toward said engaging means and having its greatest cross-sectional dimension substantially the same as the external diameter of said tubular element interposed between said engaging means and pilot-block, and an axially outwardly extending radially inwardly converging centering face formed in the inner end face of said pilot-block concentric with the axis thereof and extending from the external radially outer face thereof and being adapted to engage the external peripheral face of the adjacent end of said. tubular element, and means adapted to engage said stem and said pilot-block to maintain said tubular element in proper centered relation with said pilot-block.

4. A tool for inserting a tubular element in a bore and displacing a part in aradial direction from said bore, said tool comprising a stem adapted to extend through said tubular element, and engaging means carried by said stem and adapted to engage the adjacent end face of said tubular element at a plurality of points on opposite sides of its axis and in a single plane perpendicular to the axis of said tubular element, in combination with a pilot-block adapted to make a snug fit on said stem and freely slida-ble axially thereof, said pilotbloch having an axially tapering external face with its larger end portion presented toward said engaging means and having its greatest cross-sectional dimension of a length substantially the same as the external diameter of said tubular element interposed between said engaging means and pilot-block, and there being an axially out-- wardly extending radially inwardly converging centering face formed in the inner end face of said pilot-block concentric with the axis thereof and extending from the radially outer face of said pilot-block and being adapted to engage the external peripheral face of the adjacent end of said tubular element.

5. A tool for inserting a tubular element in a bore and displacing a part in a radial direction from said bore, said tool comprising a stem adapted to extend through said tubular element, in combination with a pilotblock adapted to make a snug fit on said stem and freely slidable axially thereof, said block having an axially tapering external face with its larger end portion adapted to be presented toward said tubular element and having its greatest cross-sectional dimension of a length substantially the same as the external diameter of said tubular element, and there being an axially outwardly extending radially inwardly converging centering face formed in the inner end face of said pilot-block concentric with the axis thereof.

6. A tool for inserting a tubular element in a bore, said tool comprising a stem adapted to extend through said tubular element, in combination with a pilot-block adapted to make a snug fit on said stem and freely slidable axially thereof, said block having an axially tapering external form with its larger end portion adapted to be presented toward said tubular element and having its greatest cross-sectional dimension of a length substantially the same as the external diameter of said tubular element, and havi ing its larger radial face formed, at a plurality of points concentric with and disposed on opposite sides of its axis, with portions extending axially outwardly and converging radially inwardly and cooperatively functioning to engage the external peripheral face of the adjacent end of said tubular element at a corresponding plurality of points concentric with and disposed on opposite sides of the axis of said tubular ele ment to center the same with relation to the tapering external face of said pilot-block.

7. A tool for inserting a tubular element in, and removing said tubular element from, a bore and displacing a part in a radial direction from said bore, said tool comprising a stem adapted to extend through said tubular element, and a cylindrical part immovable with relation to said stem and adapted to engage the adjacent end face of said tubular part at a plurality of points on opposite sides of its axis and in a single plane perpendicular to the axis of said tubular element, said cylindrical part being of substantially the same external diameter as said tubular element, in combination with a pilot-sleeve adapted to be fitted endwise on said stem and making a snug sliding fit thereon, said sleeve having a frusto-conical external face and having its portion of greatest external diameter presented toward said cylindrical part and of substantially the same external diameter as said tubular element interposed between said cylindrical part and said pilot-sleeve, there being an axially outwardly extending radially inwardly converging centering face formed in the inner end face of said pilots-sleeve concentric with the axis thereof and extending from the external peripheral face thereof and being adapted to engage the external peripheral face of the adjacent end of said tubular element to center the same, said stem having its free end portion screw-threaded and adapted to protrude axially beyond said pilot-sleeve, and a nut adapted to be turned on said screw-threaded portion of said stem to engage said pilot-sleeve and move the latter axially toward said cylindrical part to clamp said tubular element between said pilot-sleeve and cylindrical part and to maintain said tubular element in proper centered relation with said pilot-sleeve.

8. A tool for inserting and removing a tubular element in and from a bore, said tool comprising a stem adapted to extend through said tubular element, and a stop carried by said stem and having no crosssectional dimension exceeding the diameter of said tubular element and being adapted to engage the adjacent end face of said tubular element at a plurality of points on opposite sides of its axis and in a single plane perpendicular to the axis of said tubular element, in combination with a pilot-block adapted to make a snug fit on said stem and freely slidable axially thereof, said block having an axially tapering external face 1 with its larger end portion adapted to be presented toward said tubular element and having its greatest cross-sectional dimension of a length substantially the same as the external diameter of said tubular element, there being an axially outwardly extending radially inwardly converging face formed in the inner end face of said pilot-block concentric with the axis thereof and extending from the external face thereof and being adapted to engage the external peripheral face of the adjacent end of said tubular element to center the same, and means engaging said stem and pilot-block to maintain said tubular element in proper centered relation with said pilot-block.

In testimony whereof, we have signed our names to this specification at Lancaster, Pennsylanvia, this 24th day of May, 1980.

HARRY W. KULP. MARTIN C. DELLINGER. 

